:root {
  --bg: #f6f7f9; --panel: #fff; --text: #1d2330; --muted: #6b7385; --line: #e2e5ec;
  --accent: #2f5bea; --accent-text: #fff; --user: #e8eeff; --tool: #f1f3f7; --error: #c0362c;
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14171f; --panel: #1c212c; --text: #e6e9f0; --muted: #98a1b5; --line: #2b3242;
    --accent: #6f8cff; --accent-text: #10131a; --user: #26304d; --tool: #232a38; --error: #ff7b70;
  }
}
* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--text); font: 16px/1.5 system-ui, sans-serif; }
header { display: flex; justify-content: space-between; align-items: center; padding: 12px 16px; border-bottom: 1px solid var(--line); background: var(--panel); }
header h1 { margin: 0; font-size: 1.05rem; }
header form { margin: 0; }
button { font: inherit; cursor: pointer; border-radius: 8px; border: 1px solid var(--line); background: var(--panel); color: var(--text); padding: 8px 14px; }
button.primary { background: var(--accent); color: var(--accent-text); border-color: var(--accent); }
button:disabled { opacity: .6; cursor: default; }
main { display: grid; grid-template-columns: minmax(0, 3fr) minmax(0, 2fr); gap: 16px; padding: 16px; max-width: 1200px; margin: 0 auto; height: calc(100vh - 56px); }
section { background: var(--panel); border: 1px solid var(--line); border-radius: 12px; display: flex; flex-direction: column; min-height: 0; }
section > h2 { margin: 0; padding: 12px 16px; font-size: .85rem; text-transform: uppercase; letter-spacing: .04em; color: var(--muted); border-bottom: 1px solid var(--line); }
.scroll { flex: 1; overflow-y: auto; padding: 16px; display: flex; flex-direction: column; gap: 10px; }
.msg { max-width: 85%; padding: 10px 14px; border-radius: 12px; white-space: pre-wrap; overflow-wrap: anywhere; }
.msg.user { align-self: flex-end; background: var(--user); }
.msg.bot { align-self: flex-start; background: var(--tool); }
.msg.md { white-space: normal; }
.msg.md > :first-child { margin-top: 0; }
.msg.md > :last-child { margin-bottom: 0; }
.msg.md p { margin: 0 0 .6em; }
.msg.md ul, .msg.md ol { margin: 0 0 .6em; padding-left: 1.3em; }
.msg.md code { font-family: ui-monospace, monospace; font-size: .9em; background: var(--bg); padding: 1px 4px; border-radius: 4px; }
.msg.md pre { background: var(--bg); padding: 8px 10px; border-radius: 8px; overflow-x: auto; }
.msg.md pre code { background: none; padding: 0; }
.msg.error { color: var(--error); }
.hint { color: var(--muted); font-size: .9rem; }
form.send { display: flex; gap: 8px; padding: 12px; border-top: 1px solid var(--line); }
form.send input { flex: 1; font: inherit; padding: 10px 12px; border-radius: 8px; border: 1px solid var(--line); background: var(--bg); color: var(--text); min-width: 0; }
.call { background: var(--tool); border-radius: 8px; padding: 10px 12px; font-size: .88rem; }
.call b { font-family: ui-monospace, monospace; }
.call pre { margin: 6px 0 0; white-space: pre-wrap; overflow-wrap: anywhere; font-family: ui-monospace, monospace; font-size: .82rem; color: var(--muted); }
.login { max-width: 360px; margin: 12vh auto; padding: 0 16px; }
.login form { display: flex; flex-direction: column; gap: 12px; }
.login input { font: inherit; padding: 10px 12px; border-radius: 8px; border: 1px solid var(--line); background: var(--panel); color: var(--text); }
.login .error { color: var(--error); }
@media (max-width: 800px) {
  main { grid-template-columns: 1fr; height: auto; }
  section { min-height: 50vh; }
}